2008:
Overdrive The 2008 FIRST Robotics Competition Game was not only an intense high speed race, but it also involved many challenges in automation and defensive game play. Overdrive is the first FRC game to incorporate "Hybrid" mode. Hybrid is where the robot drives autonomously, but a team member known as the robocoach can also send it infrared signals to tweak it's game play.
Overdrive is played a large 27 by 54 foot carpeted racetrack with an eight foot high overpass spanning the center of the field. Two three-team alliances (red and blue) play Overdrive from opposite sides of the field. Both alliances have two 30 inch diameter trackballs that are randomly placed at the top of the overpass before the game. At the beginning of the game is a 30 second Hybrid mode. During this period, the team's Robocoach can feed the robot signals from a TV remote to help it's game play. Besides this feedback, all robots operate completely independently from their operators. If a trackball is knocked off the overpass during hybrid, then ten points are awarded to the alliance to which the ball belongs. Two points are awarded for every quarter of the track that a robot passes. At the end of the Hybrid Period, drivers take control of their robots. Every lap a robot makes earns their alliance two points, If the robot pushes a trackball around the track (herding), they will receive four points for that lap. Finally, if a teams robot "hurdles" the trackball over the overpass, it will receive eight points for that lap. Any trackballs on the overpass at the end of the match earn twelve additional points each. Penalties can also be assigned if a robot breaks any rules, such as ramming another robot, driving backwards over a quarter line, obstructing the track, etc. The alliance with the most points at the end of the match wins that match. Alliance scores are then added up to determine a teams ranking for their regional competition. After all the elimination rounds, the top eight teams get to pick the teams for their alliances in the finals. Those eight alliances then compete in the finals for the top position. The teams on the winning alliance are then sent to Atlanta to compete at the Nationals.
Based on the nature of the game, we decided that the most effective strategy was to hurdle as many balls as possible, and to control which balls were on the overpass at the end of the game, as these were worth 12 points each. We chose to create a robot with a large front "talon" that would grasp the ball, and elevate it to the height of the overpass. The talon was attached to a cable powered elevator system made out of 80/20 stock. We would mount this to a chassis with two central powered wheels and four surrounding castors. This would yield an easy 0° turn radius. It turned out that this orientation made the robot spin too easily, but we were able to control it fairly well with two joysticks. Most of the non-kit parts were all manufacture by the students at our build site, TechWorks. We also extensively used carbon fiber from another sponsor ACI. This material gives plenty of strength while also keeping weight down, which is important when you have a 120 pound weight limit. Many times, this material has kept the robot together where other pieces have failed. We finished the RoboTalon with about a day to spare for practice and shipped it.
This year, Rockford Robotics went to two competitions: The Midwest Regional in Chicago and the Wisconsin Regional in Milwaukee. In Chicago, we were able to make it into the finals, but we didn't move up much further. We did discover many problems with the current iteration of our Robot, the RoboTalon. Basically, our robot worked effectively, but it was really slow. Our challenge for the next competition was to keep our reliability, but to enhance our speed. We were able to do this by changing a spool on our claw, adding a wheel to the top of our claw to quickly pull in trackballs, and changing the motor that we used to lift the trackballs up to the overpass. We also were able to add some basic autonomous programming to help get more points during the hybrid mode. Because of these large speed boosts, we rechristened the robot, the "TurboTalon." Due to the modifications, it took us longer to get the robot functioning correctly during the competition. Despite this, we still performed much better in Milwaukee then we did in Chicago. We were able to lift balls faster, pull them into our claw faster, and move around the field with more ease. Unfortunately, we weren't noticed as much in Milwaukee, and we didn't make the finals. Overall, we greatly enjoyed the competition, and the opportunity to play with such great teams. We are also very grateful to our sponsors for making this all possible. Next year, we are going to better focus our marketing at the competitions to enhance our chances of doing even better.
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